Science Olympiad Dynamic Planet Practice Test

Aftershocks occur as a result of what?

1. The relaxation of tectonic stress post major earthquakes

2. Continued seismic activity in the same fault line

3. Human activities following an earthquake

4. The movement of ocean currents

The correct answer is: The relaxation of tectonic stress post major earthquakes

Aftershocks occur primarily as a result of the relaxation of tectonic stress following a major earthquake. When a significant earthquake strikes, it releases a large amount of energy, causing a shift in the earth's crust. This initial event alters the stress distribution along the fault line, as well as in the surrounding areas of the crust. After the main shock, the crust continues to adjust and settle into a new equilibrium state. The release of accumulated stress in this ongoing process results in aftershocks, which are typically smaller in magnitude than the initial earthquake but can still be strong and felt over the same region. The other choices do not accurately capture the primary cause of aftershocks. Continued seismic activity in the same fault line may occur, but it does not specifically pinpoint the reason for aftershocks. Human activities following an earthquake can include various forms of intervention or study but are not a direct cause of aftershocks. Finally, the movement of ocean currents is unrelated to seismic activity and its effects on fault lines.